A long time ago, when mobile telephony was very young and the idea of doing anything with your handset apart from talking seemed exquisitely futuristic, a girl I was friends with introduced me to her new boyfriend. "Here, look at this," said the boyfriend thrusting his Nokia towards me, and introducing me in turn to a bald, grinning man with a lube-slicked head whose pornographic adventures challenged my understanding of the elasticity of human anatomy. That was the worst thing I had ever seen on a phone until yesterday when, in a spirit of journalistic curiosity, I downloaded the Lulu app on to my iPhone.

'The kind of thing Lulu thinks women need to know about men are comprehended by such labels as #big.feet, #kinkyintherightways and #smellsamazeballs'

Lulu sounds like a powder-puff euphemism for ladybits, and though that's not what the app is, with its tyrannous magenta colour scheme and its relentlessly twee scrolled typeface, it epitomises exactly that kind of feminine dreadfulness. If it was a person, it would drink rose fizz and giggle that it felt "a bit naughty". What Lulu is actually is a service allowing women to rate men as relationship prospects. Sorry, not women: "By girls, for girls … strictly girls only, meaning no boys allowed," says the description on the app store, just in case anyone was under the illusion that fixing hashtags on your crushes like pins in a beetle was in any way the occupation of an emotionally mature human.

The kind of thing Lulu thinks women need to know about men are comprehended by such labels as #big.feet, #kinkyintherightways and #smellsamazeballs. It's like a stiletto stamping on the face of humanity forever while Kathy Lette screams laughing. And as far as I can tell, there's no opt-out for men who'd rather not be shagged and tagged: when I set up my account, the Facebook profile of every chap I know was dragged into the Luluverse and I was invited to comment on their eligibility. I'm sorry, guys. It didn't ask me if I wanted that to happen, never mind you.

The oddity about Lulu is that this urge to classify and categorise is stereotypically supposed to be a male trait, and there are indeed many sites dedicated to men sharing opinions about women with a view to sharing the women. Over the weekend, I read an article from the New York Observer about "artisanal hookers", which are handcrafted from traditional materials and fireblasted in a heritage stone kiln. Not really, they're just incredibly expensive. And one of the ways in which wealthy men source their farmers' market grade prostitutes is through review sites, which let johns grade girls on the fidelity of their marketing materials and the quality of their services.

I had a look at some of the write-ups on one site. They were surprisingly polite, in a Readers' Confessions way: "Lisa answered the door in a dangerously tight black dress," that sort of thing, written as though getting seconds of pleasure from the encounter (and for the prices involved, it's hard to begrudge any punter that). I don't doubt that the tone of these referrals varies wildly, but in the most simplistic way, reviewing the paid service of a prostitute strikes me as wildly more ethical than trading notes on a man who didn't realise that by entering into a brief relationship with a Lulu user, he was redefining himself as a rateable consumer product.

Lulu is gross, then, and a definite privacy threat. But is it even useful? Its data collection options are geared towards a very specific profile of female desire: #willwatchromcoms is the sole concession to culture in the "best thing I can say about him" list; #trekkie appears only in the "worst thing" options. If your idea of a good night in involves watching The Wrath of Khan followed by some #kinkyinthewrongway action, then Lulu is not going to help you in your search for Spock.

If your idea of a good night in involves another woman, forget it: Lulu is straightsville. Its hideous existence is predicated on a sniggering us-v-them dynamic, so the idea that women could be both reviewer and reviewee would blow its revolting pink world apart. The worst news for Lulu, though, is that I'm not sure women even care about this sort of crowdsourced insight into their potential dates.

My old friend's boyfriend turned up to the pub that long-ago night with his own worst thing – #collectshorrifyingpornclips and that affair outlived the rosy glow of female comradeship. Love and sex are far stranger than any checklist can accommodate.